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	hartrees
Energy at 0K	-77.255720
Energy at 298.15K	-77.255687
HF Energy	-77.163572
Nuclear repulsion energy	24.512590

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	Σ_g	3530	3395	0.00	62.75	0.24	0.39
2	Σ_g	2015	1938	0.00	103.06	0.07	0.14
3	Σ_u	3434	3303	94.81	0.00	0.00	0.00
4	Π_g	518	498	0.00	3.31	0.75	0.86
4	Π_g	518	498	0.00	3.31	0.75	0.86
5	Π_u	724	696	98.22	0.00	0.00	0.00
5	Π_u	724	696	98.22	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.680
H4	0.000	0.000	-1.680

	C1	C2	H3	H4
C1		1.2173	1.0709	2.2882
C2	1.2173		2.2882	1.0709
H3	1.0709	2.2882		3.3591
H4	2.2882	1.0709	3.3591

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP=FULL/aug-cc-pVDZ

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Calc. vs exp. Bad Vib. HF vs MP2 Bad scale factors Low excited states Oddities NaCN Is not linear FAQ Help Units Choose Units Energy Bond length Rotational Constant Moment of Inertia Dipole and Quadrupole Polarizability Explanations Hartree cm-1 Debye Credits Just show me Show me a calculated geometry Summary Using older interface Limit Basis sets Method options List Recent molecules Choose a few Molecules Number of atoms By heavy atoms Diatomics InChI Deuterated Dimers Geometry Point group Point group count Bonds types Isodesmic reactions Bad point group Multiple conformers, states Vibrations Big anharmonicity Energy Enthalpy at 0 Kelvin Similar molecules Similar Isomers Cis/trans Tautomers Multiple conformers, states Ions, Dipoles, etc. List Ions Ionization changes point group Dipole Quadrupole Polarizability Proton Affinities Index of CCCBDB Feedback Error form Wants
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All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B2PLYP=FULL/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)